package com.atguigu.gulimall.product.service.impl;

import com.atguigu.gulimall.product.service.CategoryBrandRelationService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.atguigu.common.utils.PageUtils;
import com.atguigu.common.utils.Query;

import com.atguigu.gulimall.product.dao.CategoryDao;
import com.atguigu.gulimall.product.entity.CategoryEntity;
import com.atguigu.gulimall.product.service.CategoryService;
import org.springframework.transaction.annotation.Transactional;


@Service("categoryService")
public class CategoryServiceImpl extends ServiceImpl<CategoryDao, CategoryEntity> implements CategoryService {

    @Autowired
    private CategoryBrandRelationService categoryBrandRelationService;

    @Override
    public PageUtils queryPage(Map<String, Object> params) {
        IPage<CategoryEntity> page = this.page(
                new Query<CategoryEntity>().getPage(params),
                new QueryWrapper<CategoryEntity>()
        );

        return new PageUtils(page);
    }

    /**
     * 查询商品分类，并且以树形保存
     * @return
     */
    @Override
    public List<CategoryEntity> listWithTree() {
        //1.查出所有分类
        List<CategoryEntity> categoryEntityList = baseMapper.selectList(null);
        //2.以树状组装
        //(1).找到一级分类
        List<CategoryEntity> level1Menu = categoryEntityList.stream()
                .filter(categoryEntity -> categoryEntity.getParentCid() == 0)
                .map((menu) ->{
                    menu.setChildren(getChildren(menu,categoryEntityList));
                    return menu;
                })
                .sorted((menu1, menu2) ->{
                    return (menu1.getSort()==null?0:menu1.getSort()) - (menu2.getSort()==null?0:menu2.getSort());
                })
                .collect(Collectors.toList());

        return level1Menu;
    }

    /**
     * 根据id删除
     * @param asList
     */
    @Override
    public void removeMenuByIds(List<Long> asList) {
        //TODO 1.检查当前删除的id是否被其他地方引用

        //逻辑删除
        baseMapper.deleteBatchIds(asList);
    }

    /**
     * 找到catelogId的完整路径
     *
     * @param catelogId
     * @return
     */
    @Override
    public Long[] findCategoryPath(Long catelogId) {
        List<Long> paths = new ArrayList<>();
        List<Long> parentPath = findParentPath(catelogId, paths);
        Collections.reverse(parentPath);


        return (Long[]) parentPath.toArray(new Long[parentPath.size()]);
    }

    /**
     * 级联更新所有数据
     * @param category
     */
    @Override
    @Transactional
    public void updateCascade(CategoryEntity category) {
        this.updateById(category);

        categoryBrandRelationService.updateCategoryDetails(category.getCatId(), category.getName());
    }

    private List<Long> findParentPath(Long catelogId, List<Long> paths) {
        //1.收集当前节点id
        paths.add(catelogId);
        CategoryEntity byId = this.getById(catelogId);
        if (byId.getParentCid() != 0) {
            findParentPath(byId.getParentCid(), paths);
        }

        return paths;
    }

    /**
     * 寻找子菜单
     * @param root
     * @param all
     * @return
     */
    private List<CategoryEntity> getChildren(CategoryEntity root, List<CategoryEntity> all) {
        List<CategoryEntity> collect = all.stream()
                .filter(categoryEntity -> categoryEntity.getParentCid() == root.getCatId())
                .map(categoryEntity -> {
                    categoryEntity.setChildren(getChildren(categoryEntity, all));
                    return categoryEntity;
                })
                .sorted((menu1, menu2) -> {
                    return (menu1.getSort()==null?0:menu1.getSort()) - (menu2.getSort()==null?0:menu2.getSort());
                })
                .collect(Collectors.toList());

        return collect;
    }
}